Spirometer.



No. 757,797. PATENTBD APR, 1-9, 1904. A. E. WELLS.

SPIROMETER.

APPLICATION FILED JAN. 4, 1904.

vHO MODEL.

2 i I f ll illl Hi1 Patented April 19, 1904.

UNiTn STATES PATENT OFFICE;

ARTHUR E. WVELLS, OF YORK, N. Y.

SPIROIVIETER.

SPECIFICATION forming part of Letters Patent N 0. 757,797, dated April 19, 1904.

Application filed January 4, 1904.

To all whom it may concern.-

Be it known that I, .ARTHUR E. lVnLLs, a citi- Zen of the United States, residing at New York city, Manhattan, county and State of New York, have invented new and useful Improvements in Spirometers, of which the following is a specification.

This invention relates to an improved spirometer, by means of which the volume of air exhaled from the lungs may be readily and accurately ascertained.

In the accompanying drawings, Figure 1 is a side elevation of my improved spirometer with the cylinder and inlet-tube omitted; Fig. 2, a vertical longitudinal section of the spirometer; and Fig. 3, a cross-section on line 3 3, Fig'. 1.

The letter (4 represents a circular base having an upwardly-extending annular rim to and a depending flange a", which constitutes a foot. Upon the base a is supported a transparent glass cylinder Z), between the lower end of which and the rim 6/ a packing c is interposed. The upper end of cylinder 5 supports a stepped ring (Z, which constitutes a top and is connected to the base (a by means of upright rods f. These rods are placed at the outside of cylinder 5, Fig. 3, and have threaded upper and lower ends that pass through openings of ring (Z and rim 0/, respectively. Nuts f, mounted upon the ends of rods f, securely connect the cylinder to its base and top.

WVithin the cylinder 7/ is free to move vertically a bell g, which is slightly shorter than the cylinder and has a flange 9 adapted to support the bell upon top 6? when the bell is in its lowermost position. As the cylinder 7) is transparent, it exposes the bell fully to view. The cylinder is provided with an upright transparent scale 5, along which the lower edge of the bell moves, the latter constituting the pointer. Thus by observing the reading of the scale opposite the lower edge of the bell the height to which the latter has been raised can be readily ascertained. The cylinder t is filled partly with a transparent liquid Serial No. 187,602. (No model.)

it, which constitutes a seal and prevents the escape of air around the lower edge of the bell The base a is perforated centrally for the admission of an air-exit pipe 6, which extends into the cylinder and bell and opens near the top of the latter. At its lower end the piped is by a flexible tube 2' connected to a working cylinder 7', within which moves a piston 70. The cylinder j is also connected toan air-inlet tube Z, that enters the cylinder at a distance from the tube t' and has mouthpiece l. The piston is is connected to a coin-controlled releasing mechanism, (not shown,) and when raised above tube 1? causes communication to be established between the inlet-tube land the outlet-tube e'. WVhen the piston is interposed between the tubes, (dotted lines, Fig. 2,) the communication between the latter is interrupted.

The operation will be readily understood.

- After the piston is released air blown through the mouthpiece Z will raise the piston and elevate the bell to a height corresponding to the capacity of the lungs, which may be read oil? the scale 6. When the pressure ceases, the piston descends to cut off pipe e' from tube Z, and the air from the bell escapes through the upper open end of the cylinder.

l/Vhat I claim is- In a spirometer, a glass cylinder having a transparent scale combined with a perforated base having an upwardlyextending rim and a depending flange to constitute a foot, an annular top, rods for connecting the base to the top, a bell movable within the cylinder and having a lower edge which is visible through the scale, and an air-pipe projecting-into the bell through the perforated base, substantially as specified.

Signed by me at NewYork city, (Manhattan,) New York, this 2d day of January, 1904.

ARTHUR E. WELLS. 

